High Speed Uplink Packet Access (HSUPA) is a packet-based data service in a WCDMA (Wideband Code Division Multiple Access) uplink with a typical data transmission capacity of a few megabits per second, thus enabling the use of symmetric high-speed data services, such as video conferencing, between user equipment and a network infrastructure.
An uplink data transfer mechanism in the HSUPA is provided by physical HSUPA channels, such as an E-DPDCH (Enhanced Dedicated Physical Data Channel), implemented on top of WCDMA uplink physical data channels, such as a DPCCH (Dedicated Physical Control Channel) and a DPDCH (Dedicated Physical Data Channel), thus sharing radio resources with the WCDMA uplink physical data channels. Physical L1 (Layer 1) control information is carried on an E-DPCCH that is code multiplexed with the E-DPDCH channels.
Discontinuous uplink transmission operation (uplink gating) is well suited for services like voice over IP (VoIP) having a periodic data source, such as a speech encoder producing a speech frame every 20 ms (AMR). With IP (Internet protocol) based services, a session is configured at a layer above radio (session initiation protocol, SIP, being used), so it is not known in a radio network controller (RNC) or in node B that a PS (packet switched) domain service is VoIP or any other service with periodic transmission of packets, such as push to talk over cellular (PoC). This is even more the case when using 3rd party clients like Skype, which hide the type of data actually being transmitted. This makes it difficult to determine which users could be using discontinuous uplink without their service quality being impacted.
An activated uplink gating pattern gives best gains when the uplink activity needed for maintaining the link can be synchronized with the activity of the data source. Because other periodic traffic sources, such as VoIP, can also be introduced, the only usable pattern cannot be optimized solely for VoIP use (such as PS Video). However, currently periodic traffic is treated like any other packet data stream. Uplink gating is described in 3rd Generation Partnership Project; TR 25.903, V0.2.0 (2005-11).
Therefore, a need exists to consider improvements for the radio resource control in an HSUPA system.